Re: Forth Implementations advantages and disadvantages.

From	Cecil Bayona <cbayona@cbayona.com>
Newsgroups	comp.lang.forth
Subject	Re: Forth Implementations advantages and disadvantages.
Date	2017-05-28 13:47 -0500
Organization	A noiseless patient Spider
Message-ID	<ogf5pj$10u$1@dont-email.me> (permalink)
References	(3 earlier) <ogcjbv$n7p$1@dont-email.me> <62e10459-9520-4e7b-b378-cff16e351fa7@googlegroups.com> <ogdpqo$s6n$1@dont-email.me> <ogeutn$8qh$1@dont-email.me> <ogf2ir$leh$1@dont-email.me>

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On 5/28/2017 12:52 PM, rickman wrote:
> Cecil Bayona wrote on 5/28/2017 12:50 PM:
>> On 5/28/2017 1:17 AM, rickman wrote:

> 
> All of the Lattice FPGAs have the LUT RAM available as distributed RAM 
> like the Xilinx parts.  The main Lattice FPGA lines are from licenses 
> obtained by buying the ORCA line of FPGAs from Lucent.  These licenses 
> in turn were bought by Lucent from Xilinx at a time when Lucent was 
> second sourcing the basic XC3000 and maybe the XC4000 devices.
> 
> The iCE40 parts are from Silicon Blue bought some years ago.  The basic 
> design patents on Xilinx FPGAs have expired so many functions of Xilinx 
> LUTs are available to all including distributed memory.
> 
> 
>>
>> Stack machines is my current line of interest so far the richest machine
>> I've used uses the following registers;
>>
>> TOS top of Data Stack
>> TRS top of Return Stack
>> W a temporary register
>> IX an Index register to use with memory access specially in accessing 
>> arrays
>> of data.
>> IP Instruction Pointer
>>
>> Add to that a Data and Return Stack but those are not registers but their
>> pointers use a small register not directly accessible.
>>
>> Not a whole lot of registers specially when compared to a MSP430 CPU 
>> with 16
>> general registers, or an ARM CPU with 32 general registers.
> 
> Big difference...  The registers in a stack machine need to be separate, 
> so they use FFs for the registers and LUTs for the input and output 
> muxes.  A RAM is a bunch of registers with output muxes to share the 
> output bus.  A register file can be efficiently implemented in a small 
> RAM which utilizes the internal muxes rather than LUTs.
> 

A normal register file uses RAM because they are all wired the same but 
a Forth register needs to be FF because the registers are not wired to 
the same places? I assume then that in a regular register file CPU the 
use of dual ported RAM allows the use of two register at the same time.

> Regardless of how many registers a design has, the real driver of logic 
> usage is usually muxes.  You can have one register (top of data stack 
> for example) which is fed by many sources and the mux will end up being 
> huge.  I know this from experience... ;)
> 
> The way to keep your design small and efficient is to focus on the 
> micro-ops required to implement an instruction to keep these 
> interconnects to a minimum.
> 

Since the CPUs that I'm interested in for the most part single clock to 
execute an instruction types then one ends up using an lot of muxes.

>> Using PAC (Portable Assembler Code) mnemonics when moving the code to
>> another CPU the primitives and other assembler code does not need to be
>> changed, only the assembler needs to be changed and that would need 
>> changes
>> no matter what scheme one uses, so it is simpler to port using a PAC
>> assembler. It's not the traditional way where you have to re-write all 
>> the
>> assembly code but times are changing we are not in the 70s anymore.
> 
> You seem to be laser focused on the idea that rewriting the tool has to 
> be easier than rewriting the code.  I don't know of any portable 
> assemblers that work the way you describe.  So you will need to write 
> this from scratch.

That is because changing the PAC assembler is a fairly simple task 
versus re-writing all the primitives. Don't forget that in the 
conventional way you have to do massive changes to the assembler and 
then you have to rewrite all the primitives and associated assembler 
code. While using PAC all we need to change is the code generated by the 
assembler and the job is done.

That is a lot easier than a rewrite of the assembler and all the code 
words. In either case the tools have to be changed there is no getting 
away from that, with PAC the changes are fewer and simpler. In either 
case one needs to change a few specific items having to do with I/O and 
CPU items like writing to Flash so neither has an advantage there.

> 
> 
>> I tend to think that this is a superior way to write a Forth that is
>> efficient and easy to port qualities that with traditional assemble 
>> code are
>> at odds with each other. Mind you no matter what one uses there are 
>> some CPU
>> specific items that need to be update such clock management and I/O but
>> those need changing with a new CPU no matter what way one uses so it
>> something to be dealt with.
> 
> I don't see any advantage at all.  Either way you need to generate 
> native code for the processor you are using.  One way you recode a few 
> Forth words which gives you native code *and* gives you an opportunity 
> to optimize the code easily.  The other way you have existing "portable" 
> assembler code which now has to be translated/compiled to native code by 
> a tool that needs to be rewritten for the target processor.  Then if you 
> want optimized code you likely need to rewrite the "portable" assembly 
> code.

That is because I'm laser focused as you mentioned, PAC code can be 
optimized just the same as native code, the assembler generates native 
code its just that the mnemonics are the same for many CPUs so the 
assembler needs fewer changes to it when porting to a new CPU.
> 
> I am ready to return to my self-assigned task of documenting Mecrisp on 
> the MSP430.  Let me know how your project goes.  If you need any advice 
> on FPGA CPUs, I'm happy to lend my experience.
> 
Not an exciting task but one that needs to be done.


-- 
Cecil - k5nwa

Thread

Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-26 14:49 -0500
  Re: Forth Implementations advantages and disadvantages. minforth@arcor.de - 2017-05-26 13:17 -0700
    Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-26 17:53 -0500
      Re: Forth Implementations advantages and disadvantages. Raimond Dragomir <raimond.dragomir@gmail.com> - 2017-05-26 22:31 -0700
        Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 00:57 -0500
  Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 01:09 -0400
    Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 00:59 -0500
      Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 02:09 -0400
        Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 09:35 -0500
          Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 12:22 -0400
            Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 11:53 -0500
              Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 13:13 -0400
              Re: Forth Implementations advantages and disadvantages. David Schultz <abuse@127.0.0.1> - 2017-05-27 12:24 -0500
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 13:13 -0500
                Re: Forth Implementations advantages and disadvantages. David Schultz <abuse@127.0.0.1> - 2017-05-27 13:33 -0500
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 14:53 -0400
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 14:44 -0500
                Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-28 10:09 +0200
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-28 12:57 -0400
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 12:14 -0500
                Re: Forth Implementations advantages and disadvantages. Paul Rubin <no.email@nospam.invalid> - 2017-05-28 16:11 -0700
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-29 02:11 -0400
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 01:54 -0500
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-29 03:22 -0400
    Re: Forth Implementations advantages and disadvantages. Joel Rees <joel.rees@gmail.com> - 2017-05-28 15:46 -0700
  Re: Forth Implementations advantages and disadvantages. Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-27 01:23 -0500
    Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 09:29 -0500
      Re: Forth Implementations advantages and disadvantages. Paul Rubin <no.email@nospam.invalid> - 2017-05-27 11:36 -0700
        Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 14:25 -0500
      Re: Forth Implementations advantages and disadvantages. Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2017-05-27 21:58 -0400
    Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-27 11:20 -0700
      Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 15:20 -0400
      Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 14:20 -0500
        Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 18:33 -0400
          Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 18:50 -0500
            Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-27 20:13 -0400
          Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-28 10:23 +0200
            Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 12:26 -0500
              Re: Forth Implementations advantages and disadvantages. Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-30 04:22 -0500
                Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-30 11:49 +0200
                Re: Forth Implementations advantages and disadvantages. Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-05-30 05:07 -0500
                Re: Forth Implementations advantages and disadvantages. Lars Brinkhoff <lars.spam@nocrew.org> - 2017-05-30 18:58 +0200
            Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 12:28 -0500
              Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-28 20:14 +0200
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 14:08 -0500
                Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-29 10:52 +0200
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 12:50 -0500
                Re: Forth Implementations advantages and disadvantages. Alex <alex@rivadpm.com> - 2017-05-29 19:06 +0100
        Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-27 20:00 -0700
          Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-27 22:29 -0500
            Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-27 22:10 -0700
              Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 11:22 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-28 14:45 -0700
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-28 18:25 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 21:43 -0500
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-06-01 11:27 -0500
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-06-01 12:50 -0400
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-06-01 12:47 -0500
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-06-01 16:23 -0400
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-06-01 16:32 -0400
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-06-01 12:08 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-06-01 21:47 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-06-02 06:34 -0700
                Re: Forth Implementations advantages and disadvantages. foxaudioresearch@gmail.com - 2017-06-02 07:13 -0700
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-06-02 07:57 -0700
                Re: Forth Implementations advantages and disadvantages. albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-06-03 02:17 +0200
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 21:07 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-28 21:48 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 00:52 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-29 09:17 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 12:16 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-29 19:21 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 23:13 -0500
                Re: Forth Implementations advantages and disadvantages. Paul Rubin <no.email@nospam.invalid> - 2017-05-30 01:07 -0700
                Re: Forth Implementations advantages and disadvantages. Alex <alex@rivadpm.com> - 2017-05-30 15:54 +0100
                Re: Forth Implementations advantages and disadvantages. Alex <alex@rivadpm.com> - 2017-05-29 19:02 +0100
                Re: Forth Implementations advantages and disadvantages. Raimond Dragomir <raimond.dragomir@gmail.com> - 2017-05-29 11:06 -0700
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-29 19:29 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 23:01 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-30 14:53 -0700
                Re: Forth Implementations advantages and disadvantages. Paul Rubin <no.email@nospam.invalid> - 2017-05-29 13:59 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 17:03 -0500
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-29 19:37 -0700
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-29 22:52 -0500
            Re: Forth Implementations advantages and disadvantages. Mark Wills <markwills1970@gmail.com> - 2017-05-28 11:49 -0700
              Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 14:12 -0500
              Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-29 02:35 -0400
          Re: Forth Implementations advantages and disadvantages. jim.brakefield@ieee.org - 2017-05-27 21:04 -0700
            Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-27 21:56 -0700
              Re: Forth Implementations advantages and disadvantages. jim.brakefield@ieee.org - 2017-05-28 01:10 -0700
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-28 13:21 -0400
                Re: Forth Implementations advantages and disadvantages. jim.brakefield@ieee.org - 2017-05-28 11:53 -0700
                Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-28 15:09 -0700
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-29 02:40 -0400
                Re: Forth Implementations advantages and disadvantages. jim.brakefield@ieee.org - 2017-05-29 13:10 -0700
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-30 00:57 -0400
          Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-28 02:17 -0400
            Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 11:50 -0500
              Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-28 13:52 -0400
                Re: Forth Implementations advantages and disadvantages. Cecil Bayona <cbayona@cbayona.com> - 2017-05-28 13:47 -0500
                Re: Forth Implementations advantages and disadvantages. rickman <gnuarm@gmail.com> - 2017-05-29 03:19 -0400
              Re: Forth Implementations advantages and disadvantages. hughaguilar96@gmail.com - 2017-05-28 15:40 -0700
  Re: Forth Implementations advantages and disadvantages. Joel Rees <joel.rees@gmail.com> - 2017-05-28 16:31 -0700
    Re: Forth Implementations advantages and disadvantages. Joel Rees <joel.rees@gmail.com> - 2017-05-28 20:17 -0700
      Opinions on a C language header for words? Joel Rees <joel.rees@gmail.com> - 2017-05-28 21:38 -0700

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